ISO 8746:2025

Overview

ISO 8746:2025 specifies the characteristics and dimensional requirements for grooved pins with round head and full‑length diamond grooves (nominal diameters 2 mm to 20 mm). It covers pins with a pilot point (PL) or an optional chamfer point (CH), manufactured in steel or stainless steel, and intended primarily for locking two or more parts with easy installation and high pull‑out resistance due to the pin’s elastic fit. General functional principles and common requirements for grooved pins are given in ISO 13669.

Key topics and technical requirements

• Scope and function: Pins for locking parts; pilot/chamfer points facilitate installation and control fit.
• Dimensions and tolerances: Detailed dimensional tables and figure for sizes 2–20 mm (head diameter, expanded diameter, lengths, underhead distances). Dimensions apply prior to any coating.
• Points and grooves: Three full‑length diamond grooves; grooves closed at pilot point and open at chamfer point; groove angles referenced to ISO 13669.
• Material and surface condition:
  • Base materials: steel (symbol St) and stainless steel grades (A1, A2, A4, C1, F1).
  • Coatings and finishes referenced: electroplated (ISO 4042), zinc‑flake (ISO 10683), phosphate conversion (ISO 9717), and passivation (ISO 16048).
  • Other materials (e.g., hardened steels, brass, aluminium) permitted by agreement.
• Mechanical and inspection requirements: Mechanical/physical properties, expanded diameter control and pin straightness, hardness and shear resistance referenced to ISO 13669 and acceptance inspection to ISO 3269.
• Labelling and designation: Package labelling must reference ISO 8746, nominal d × l, material symbol/grade, point option (CH), finish/coating, manufacturer ID, lot number (ISO 1891‑4) and quantity. Standard designation examples are provided.

Applications and users

ISO 8746 pins are widely used where reliable, repeatable locking and high pull‑out resistance are needed:

• Mechanical designers and OEMs (automotive, machinery, industrial equipment)
• Fastener manufacturers and suppliers
• Quality and procurement teams specifying fastener requirements
• Assembly engineers and maintenance technicians seeking easy installation (pilot/chamfer point) These pins are suitable for applications requiring a secure elastic interference fit and consistent acceptance inspection.

Related standards

• ISO 13669 - Grooved pins - General requirements (functional principles, inspection)
• ISO 3269 - Acceptance inspection
• ISO 3506‑6 - Stainless steel selection for fasteners
• ISO 4042, ISO 9717, ISO 10683, ISO 16048 - Coating and surface treatments
• Other grooved‑pin product standards in the ISO 8739–8747, 13670, 13672 series

Keywords: ISO 8746, grooved pins, round head, diamond grooves, pilot point, chamfer point, fasteners standard, pull‑out resistance, ISO 13669, stainless steel fasteners.